Aim The internet has rapidly developed to become a default information source for parents when searching for information about their child's medical condition. This study aims to understand how parents use, search for and appraise the relevance and credibility of online information relating to children's health. Methods This research involved a practical task with parents of in‐patients with subacute health conditions at The Children's Hospital at Westmead. Each was presented with a scenario detailing symptoms of a paediatric health condition and asked to search for online health information on their mobile device. Participants' search was video‐recorded. A semi‐structured interview was then conducted to explore participants' use, search and appraisal of online health information. Interview audio recordings were transcribed verbatim and analysed using inductive thematic analysis. Videos of practical tasks were analysed using an observation checklist. Results Twenty‐two parents participated. Four themes were identified: Wide spectrum of online health information utilisation, techniques in searching for online health information, appraising relevance and appraising credibility. Most parents used online health information flexibly in conjunction with consultations with health professionals, depending on assumptions about the severity of their child's condition, availability of health professionals and relationship with their child's doctor. Most focused on website titles and descriptions more than website sources when selecting a website. Conclusion Most parents exhibited a wide use of online health information utilisation, from minimal to extensive. There are disparities between parents' perceived knowledge and performance during search and appraisal, emphasising the need for education to improve parents' eHealth literacy.